Generally, the vehicular side panel structure includes a side outer panel provided on a vehicle exterior side and a side inner panel provided on a vehicle interior side. The side outer panel includes an upper frame portion including an upper portion of a front pillar outer, a roof rail outer, a rear pillar outer, and a rear fender panel, a lower frame portion including a lower portion of the front pillar outer and a side sill outer, a center pillar outer that joins the upper frame portion to the lower frame portion, and a side sill garnish that covers the side sill outer of the lower frame portion.
The lower frame portion is joined to the upper frame portion, thereby forming a side outer panel frame portion, and the side outer panel frame portion is joined to a center pillar outer and the side sill outer covers the side sill garnish. The upper frame portion is generally formed of a steel sheet, and the lower frame portion and the center pillar outer are formed of a high tensile steel sheet or the like. The side sill garnish is formed of resin.
In the above side panel structure, the roof rail outer of the side outer panel frame portion is formed of a standard steel sheet which is easy to be press-molded. Therefore, a sharp form can be achieved by press working, and a gap generated adjacent to a door can be reduced, thereby improving appearance property. Since the center pillar outer of the side outer panel is formed of a high strength steel sheet, it is possible to exert bearing force against a side collision load (see JP 2011-195107, for example).
In the vehicular side panel structure disclosed in JP 2011-195107, optimal material can be selected for the upper frame portion including the upper portion of the front pillar outer, roof rail outer, rear pillar outer, and rear fender panel, the lower frame portion including the lower portion of the front pillar outer and the side sill outer, and the center pillar outer that joins the upper frame portion to the lower frame portion. However, since the side outer panel are divided into the upper frame portion, lower frame portion and center pillar outer, and these the upper frame portion, lower frame portion, and center pillar outer are formed in a joined manner, seams are generated at the joining parts of these components.
It is necessary to apply sealer to the seams generated at the joining parts of these components in order to prevent rainwater penetration. This sealer applying work is quite difficult because it is manually carried out, and at the same time the seams deteriorate the external appearance. An external surface shape of the side sill cannot be formed only by the side sill outer, and therefore the side outer panel has to be covered with the side sill garnish which is a separate body. Further, since the roof rail outer of the upper frame portion is formed of the standard steel sheet, a reinforcing member is added to increase strength, thereby increasing the weight.